Docks

Biology of Docks

There are over 200 species of docks worldwide, with 12 species in Ireland. The two most common and most damaging are:

Rumex obtusifolius

Rumex crispus

Broad Leaved Dock

Curled Dock

The problem with docks in grassland is that they are well adapted to modern farming techniques. They germinate throughout the year and grow from seed as well as root stocks. They compete strongly with the grass but have only 65% of the feed value of grass. They are also unpalatable to stock.

Seed

One broad-leaved dock can produce 60,000 seeds

One curled dock can produce 40,000 seeds

Seed is spread by wind, water and slurry

They are viable in the soil for up to 80 years

There are 12.5 million seeds/ha in the top 15cm of soil

Docks will produce seed even after cutting

Roots

They have a tap root and secondary root systems

Shoots grow from root sections

The roots are very long

Docks are ideally suited to the conditions created in intensively managed grassland and particularly cattle regimes. Ideal conditions for grass growth are also ideal for docks: moist, fertile soils with moderate to high levels of nitrogen.

Dock and chickweed seeds can pass undamaged through silage, the stocks’ digestive system and slurry. They are therefore spread very effectively by modern farming practices.

In the slurry the seeds are effectively coated in nutrient ready to germinate and grow.

Lax/open swards resulting from poaching, over-grazing, winter kill, pest damage and lack of tillering in shorter term leys all provide space for seeds to germinate and become established.